9.3.1 ABSTRACT: CYTOGENETICS Director: Betsy Hirsch, Ph.D. The Cytogenetics shared resource provides cell culture, karyotype analysis, and molecular cytogenetic services (including fluorescence-in-situ-hybridization and oligonudeotide array based comparative gendmic hybridization) for evaluation of human and animal cells. The Cytogenetics Core has worked with 20 different investigators representing five different programs within the Cancer Center. Over the past five years, the Core has expanded its services to meet the needs of these investigators. Examples include detailed chromosome breakage studies of mouse and human cells for evaluation of genes involved in DMA repair and maintenance of chromosome stability, sequential G-banding to SKY and FISH for mapping of transposon insertion sites, and array-CGH for the evaluation of subtle genomic copy number changes. These analyses have provided novel information to investigators that is pivotal to their future research programs. In addition, the Core has provided hundreds of conventional karyotype analyses as critical quality control measures for experiments involving genetically manipulated cells or populations of cells that have been expanded in-vitro. Karyotype verification is often a prerequisite for publication of such work: With an expanding repertoire of techniques, the Core has also focused on consultative assistance in experimental design and selection of cytogenetic and/or molecular cytogenetic techniques. Significant time is devoted to personal meetings with researchers to discuss the results and interpretation of analyses, and provide direction for future research.